Furnace



J. F. FORMAN Dec. 1, 1936.

FURNACE 4 Sheets-Sheet l Filed May 17, 1935 INVENTOR \LEFORMAH SDI WW!ATTORNEY Dec. 1, 1936.

J. F. FORMAN 2,062,357

FURNACE Filed May 17; 1935 4 Sheets-Sheet 2 INVENTQR J.F. FORMANATTORNEY J. F. FORMAN Dec. 1, 1936.

FURNACE Filed May 17, 1955 J 4 Sheets-Sheet 3 INVENTOR L'FlF ORMANATTORNEY Dec. '1, 1936. J MA 2,062,357

FURNACE Filed May 17, 1955 4Sheets-Sheet 4 J-EF'ORMAN .ATTORNEY EINVENTOR Patented Dec. 1, 1936 UNITED STATES PATENT OFFIQE ApplicationMay 17, 1935, Serial No. 22,050 In Canada April 18, 1935 7 Claims.

This invention relates to improvements in furnaces and has, for itsprincipal object, the provision of an efficient and economical furnaceconstructed mainly of standardized sheet metal sections capable of beingwelded or otherwise secured in assembled relation with a minimum amountof time and labor.

Other objects, advantages and characteristic features of the inventionwill be more readily understood from the following detailed descriptiontaken in connection with the accompanying drawings, in which- Fig. l isa front view of a furnace constructed in accordance with this invention.

Fig. 2 is a rear view.

Fig. 3 is a top plan view.

Fig. 4 is a central vertical sectional View taken along the line 44 ofFig. 3.

Fig. 5 is a section along the line 5-5 of Fig. 4..

Fig. 6 is a front elevation of the grate assembly with certain of thegrate sections removed.

Fig. 7 is a top plan View of the grate assembly with certain of thegrate sections removed.

Fig. 8 is a top plan view of the grate shaking spindle on which thegrate sections are supported.

Fig. 9 is a bottom plan view of said spindle.

Fig. 10 is a top plan view of the main grate supporting bar.

Fig. 11 is a view similar to Fig. 4 but showing a modified type offurnace designed for use as an oil or gas burning furnace.

Fig. 12 is a plan View of a modified grate'assembly, and

Fig. 13 is a vertical sectional View showing the grate assembly of Fig.12 installed in a furnace.

The casing wall of the furnace appearing in Figs. 1 to 4 inclusivecomprises two cylinder 5 and 6 spaced apart to define an interveningannular water space I, each cylinder being formed 'by rolling a sheet ofsuitable gauge metal into cylindrical form and then welding thelongitudinal edges of the sheet. A bottom ring 8 is welded to the lowerends of the cylinders 5 and 6 and serves to close ofi the lower end ofthe water space 1. Above the plate 8 the cylinders 5 and B are providedwith suitable apertures in which :are fitted the fire door 9, the ashpit door l0 and the ash pit damper structure H. The upper end ofcylinder 8 is welded to a top plate l2 provided with a central aperturel3 through which coal or other fuel is introduced into a fuel magazine[4 provided in the upper part of the furnace. The opening l3 ispreferably .bounded by an annular metal frame or rim l'3w The fuelmagazine It is bounded by inner and outer-sheet metal cones l1 and IS,the former having its upper edge welded to the upper edge portion of theouter casing cylinder 6 and the latter having its upper edge welded tothe upper edge of the inner casing cylinder 5. The cones ll and I 8 arespaced apart todefine an intervening annular water space I!) closed atthe bottom by a ring IQw welded to the lower ends of the cones. Theupper portion of the water space I0 communicates with the upper portionof the water space '1' via an opening provided above the upper end ofcylinder 5 Which is shorter thancylinder 6. The lower portion of thewater space I9 is also placed in communication with the water chamber 1at a point intermediate the height of the latter. This is accomplishedthrough the provision of a Welded pipe 20-0011- necting an opening 2i inthe lower portion of the cone l8 with an opening 22 in the casingcylider 5.

A heat economizer comprising a casing 23, substantially U-shaped inhorizontal cross section, is welded to the casing cylinder 5 at the rearof the furnace. The rear and side walls of the casing 23 are formed byinner and outer sheet metal plates 24 and 25 defining an interveningwater space 26 which communicates with the water space 1 via suitableopenings 21 provided in the casing cylinder 6 (see Fig. 5). The casing23 is dividedby a horizontal partition 28 into an upper compartment 20and a lower compartment 30. The compartment 29 contains a hot waterservice coil 3| and is in communication with the water chambers l and I9through an opening 32 formed in the upper portion of the casing cylinder6. Compartment 29 is also part of water space 25 and is provided withoutlets 33,34, and 35 through which the hot water circulating upwardlythrough the water chambers 1, I9, and 25 is delivered to the pipes andradiators of a hot water circulating system, the return pipes of whichare connected to the lower, portion of the water chamber l9 at theinlets 3 6 and 31 provided for this purpose (see Figs. 3 and 5).

The compartment 30 of casing 23 is provided with a vertical bafflecomprising an adjustable lower portion 40 and a movable upper damperportion 4!. The damper portion M is mounted .on a horizontal pivot 42 sothat it may be swung from the full to the dotted line position shown in.Fig. 4. When the damper portion 4| is in the with the lower adjustableportion 40 to provide a tortuous passage 55 leading from the smokeoutlet M of the furnace to a smoke outlet 45 provided at the upper rearportion of casing 23. When the damper portion H of the: bafiie is movedto the horizontal position indicated by dotted lines in Fig. 4 the smokeor products of combustion escaping from the furnace outlet M arepermitted to pass upwardly through the smoke outlet 45 of the casing 23without traversing the tortuous passage 43. As here shown, the lowerbaflle portion 49 is composed of two sections lfla and 49b held togetherby pin and slot connections 560 or other fastening means permittingadjustment to vary the effective length or depth of the battle.

The compartment 35 of casing 23 is closed at the bottom by a wall 96provided with an opening 4! controlled by a draft damper 38 adapted tobe operated in any suitable manner. In place of or in addition to theheating coil 3| I may provide a heating coil 49 in the water chamber I!of the fuel magazine M.

The grate structure of the furnace is best shown in Figs. 6 to 10inclusive. It comprises a plurality of segment-shaped grate sections 50assembled in conical formation. The upper end of each grate section isprovided with a depending projection 51 fitted in one of the arms 52 ofa cross-shaped slot formed in the head 53 of a vertical spindle 54.which is journalled in the main grate supporting bar 55. As shown moreclearly in Fig. 6, the head of the spindle 54 and the main supportingbar 55 are provided with intermeshing ratchet teeth 55 and 51 wherebythe spindle, together with the grate sections 56 are raised and loweredwith an abrupt shock to shake the grate when the spindle and grate arerotated as hereinafter described. Below the main supporting bar 55 thespindle 54 is equipped with two hub members 58 and 59 provided withintermeshing ratchet teeth 66 and 6!. The hub 59 is fixed againstturning movement on the spindle by means of a pin 52 or other fasteningmeans. I-Iub 58 is loosely mounted on the spindle 54 so that it iscapable of independent turning and axial movement. This hub is alsoprovided with a crank arm 63 having a slot 64 at its outer end throughwhich extends an operating rod 65 slidably mounted in suitable bearings66 and 66a, the latter being formed in the bar 55. The operating rod 65is provided with abutments 69 through the medium of which the crank arm63 is operated to rotate the hub 58 in response to axial movement of theoperating rod 65 which is provided with a handle 65a at its front end.When the crank arm 63 is moved back and forth by the rod 65 the ratchetteeth 65 of the hub 58 co-operate with the ratchet teeth 6! of hub 59 torotate the spindle and grate. Through co-operation of the ratchet teeth56 and 5? this rotation of spindle 54 and grate 50 results in an abruptvertical shaking movement of the grate sections 56 as ratchet 56 slipsover ratchet 5'! and as the grate sections are rotated by ratchets 69and 6! The ends of the main grate supporting bar 55 are fitted inchannel brackets 6'1 secured to opposite sides of the furnace casing.The bar 55 may be supported at different elevations in the channelbrackets 61 by passing pins 69 through selected openings 19 and Hprovided, respectively, in the channel brackets 6'l and in the bar 55.

In Fig. 11 I have shown a modified type of furnace adapted to be used asan oil or gas burning furnace. In this case fuel magazine [4 is replacedby a hot water reservoir 13. This reservoir is formed by an invertedsheet metal cone 14 having its upper end welded to the upper end of thecasing cylinder 5 so that the upper part of the reservoir is in directcommunication with a water space 1. The bottom of the reservoir isclosed by a welded plate 15 and is in communication with an intermediateportion of the water space 1 through the medium of a pipe 16 connectingan opening 11 in the cone 14 with an opening 58 in the casing cylinder5. The top of the furnace shown in Fig. 11 is closed off by a top plate19 welded to the casing cylinder 6 and provided with outlets throughwhich hot water is delivered to the piping and radiators of a hot watercirculating system, the return pipes of which are connected to thebottom of the water space i as previously described in connection withFigs. 1 to 4 inclusive. The furnace shown in Fig. 11 is also providedwith a heat economizer 23 that is sub stantially the same as thatpreviously described.

A modified form of grate structure is shown in Figs. 12 and 13. In thiscase the conical grate comprises half sections 82 and 83 bolted togetheras indicated at 64. At predetermined points in its circumference eachhalf section of the grate is provided with vertical slots 86, 81, and88, the upper end 81a of the slot 8! being positioned above the upperend 880. of the slot 88 but below the upper end 86a of the slot 86. Theupper ends 86a, 81a, and 88a of the slots of each series thus formvertical offset supporting surfaces adapted to be selectively engagedwith one of a series of supporting lugs 89 to support the grate atdifferent elevations. In Fig. 13 the grate is shown arranged with thelugs 89 received in the lower slots 88 so that the grate is thussupported at its lowest level. If it is desired to lower the grateslightly this may be accomplished by changing the position of the grateso that the lugs 89 are received in the slots 81. To support the grateat its lowest level, the lugs 89 are engaged in the slots 86. The gratemay be raised and turned to bring the desired slots over the lugs 89 bymeans of a bar or other tool X inserted through the top projections 99aof the grate. The lugs 89 are provided with base portions 90 welded orotherwise secured to the inner wall 5 of the furnace casing. These lugsare also provided with recesses 9| seating a removable ring 92substantially bridging the gap between the furnace wall 5 and theperiphery of the grate structure.

Having thus described my invention, what I claim is:

1. A furnace comprising a casing formed. by inner and outer sheet metalcylinders spaced apart to define an intervening water space closed offat the lower ends of said cylinders, a fuel magazine in said casingbounded by spaced inner and outer conical shells of gradually decreasingcircumference toward their lower ends, said inner shell having its upperend abutting and directly secured to the upper end of the outer casingcylinder and said outer shell having its upper end likewise abutting anddirectly secured to the upper end of the inner casing cylinder, thespace between the lower ends of said shells being bridged by a closurering and. a single conduit connection between the lower portion of thespace between said shells and an intermediate portion of the spacebetween the casing cylinders.

2. In a hot water furnace construction the combination of inner andouter sheet metal cylinders spaced apart to define an intervening waterspace closed ofi at the lower ends of the cylinders,

said outer cylinder being of sufficient length to project above theupper end of the inner cylinder, spaced inner and outer conical shells,of gradually decreasing circumference towards their lower ends,surrounded by the upper portions of said cylinders, the upper end of theinner shell being butted against and directly secured to the outercylinder and the upper end of the outer shell being likewise buttedagainst and directly secured to the inner cylinder, said shells formingbetween them a supplementary water space closed off at the lower ends ofthe shell, the upper portion of said supplementary water space being indirect communication with the upper portion of the water space betweenthe cylinders and a pipe connection between the lower portion of thesupplementary water space and an intermediate portion of the water spacebetween saidcylinders.

3. A furnace as set forth in claim 1 provided with an external verticalcasing attached to the outer cylinder of the furnace, said verticalcasing having double walls defining a supplementary water space indirect communication with the water space of the furnace casing andmeans whereby products of combustion are passed from the furnace casingthrough the external casing to heat the Water contained in saidsupplementary space.

4. A furnace as set forth in claim 1, provided with a gas outlet leadingthrough the double walled casing, an external vertical casing attachedto the outer cylinder of the furnace casing over the gas outlet toreceive the gases therefrom, said external casing having, double wallsdefining a water space in direct communication with the water space ofthe furnace casing through openings in the outer cylinder of the furnacecasing, said cylinder forming the inner wall of the external casing, anda gas outlet in the outer wall of said casing.

5. A furnace as set forth in claim 1, provided with a gas outlet leadingthrough the double walled casing, an external vertical casing attachedto the outercylinder of the furnace casing and mounted over the gasoutlet to receive the gases therefrom, said external casing havingdouble walls defining a water space which is directly connected throughopenings in the outer cylinder wall to all the previously mentionedwater spaces and a gas outlet leading from the external casing. V

6. A furnace as set forth in claim 1, provided with a gas outlet leadingthrough the double walled casing, an external vertical casing attachedto the outer cylinder of the furnace casing over the gas outlet toreceive the gases therefrom, said external casing having double wallsdefining a water space in direct communication with the water space ofthe furnace casing through openings in the outer cylinder of the furnacecasing, said cylinder forming the inner wall of the external casing, agas outlet leading from the external casing, and a partition arranged insaid external casing to provide a tortuous gas passage between the gasoutlets of the furnace and casing.

7. A furnace as set forth in claim 1 provided with a. gas outlet leadingthrough the double walled casing, an external vertical casing attachedto the outer cylinder of the furnace casing and mounted over the gasoutlet to receive the gases therefrom, said external casing havingdouble walls defining a water space which is directly connected throughopenings in the outer cylinder wall to all previously mentioned waterspaces, a gas outlet leading from the external casing and a verticallyadjustable partition ar-- ranged in said external casing to provide atortuous gas passage between the gas outlets of the

